Aortic valvuloplasty under echocardiographic guidance in a minor infant at a national referral center in Peru: case report

ABSTRACT Aortic valve stenosis is a congenital heart defect that causes a fixed left ventricular outflow obstruction with a progressive course. Symptomatology in neonates and young infants resembles congestive heart failure. In addition, the diagnosis of this condition is made by imaging, through echocardiography. On the other hand, treatment can be surgical or interventional under fluoroscopic guidance, depending on the hospital in which it is performed. We describe the case of a minor infant patient who presented severe aortic valve stenosis; however, the fluoroscopy equipment was not available at the time of the emergency to perform the appropriate procedure, therefore, an aortic valvuloplasty was performed under echocardiographic guidance without complications.


Introduction
Aortic valve abnormalities represent 3.5 to 5% of all cardiac defects, where most cases show progressive worsening over time (1,2) .According to biomedical literature, isolated critical aortic stenosis is uncommon and usually associated with other left-sided heart lesions, such as aortic coarctation, left ventricular hypoplasia, ventricular septal defects, and mitral valve pathology (2) .
In neonates and younger infants, critical aortic valve stenosis presents with signs of low cardiac output and left ventricular dysfunction.In these cases, it is necessary to keep the ductus arteriosus open using prostaglandins, provide inotropic support to improve systemic perfusion, and, in most cases, respiratory support (2) .Regarding echocardiographic evaluation, not only the gradient across the aortic valve but also left ventricular function should be assessed, and possible associated lesions should be ruled out.Critical aortic valve stenosis in newborns was associated with high morbidity and mortality in the past.However, it is currently associated with low morbidity and mortality, especially in centers where a higher volume of patients is attended (3) .In fact, procedure-related mortality is reported in 3.0 to 4.5% of patients (2) .Interventional treatment should be performed in patients with normal cardiac output and a peak gradient greater than 75 mmHg and a mean gradient greater than 40 mmHg, without considering the Under echocardiographic guidance, the balloon was inflated using an insufflation syringe to 4 ATM twice for a duration of ten seconds.Finally, the patient tolerated the procedure without complications (Figures 4A and 4B; Video 1).
gradient in patients with low cardiac output or severe left ventricular dysfunction (4) .Specifically, the treatment of a patient with aortic valve stenosis can be carried out through surgery (5) or cardiac catheterization (2) under fluoroscopic guidance and, currently, under echocardiographic guidance (6) .
Aortic valvuloplasty under echocardiographic guidance is a valid alternative and would have the advantage of avoiding the use of radiation and contrast agents (6) , considering that patients in critical condition may have renal injury due to systemic hypoperfusion.Therefore, we present the case of a young infant patient who presented with severe aortic valve stenosis and underwent aortic valvuloplasty under echocardiographic guidance as a therapeutic option.

Case Report
Male patient, 1 month and 24 days old, weighing 4 kg, born by normal delivery, non-syndromic, and without complications.
The mother reports that one week prior, the infant experienced increased sweating and signs of respiratory distress, prompting a visit to a peripheral hospital and subsequently to our institution through the emergency department.Upon admission to our institution, he was admitted to the Intensive Care Unit with signs of low cardiac output, without a precise cardiovascular diagnosis.
As part of the auxiliary examinations, a chest X-ray was performed, showing signs of cardiomegaly with pulmonary vascular congestion (Figure 1).Likewise, an echocardiography was performed, revealing a bicuspid aortic valve with dysplastic leaflets, dome-shaped opening, with a Z score of -1 standard deviation for the aortic annulus, maximum systolic gradient across the aortic valve of 79 mmHg and mean gradient of 52 mmHg (Figures 2A, 2B, and 3

Discussion
In patients with aortic valve stenosis at early ages, each cardiac surgical group has adopted either surgery (7) or interventionism as the initial management method to relieve obstruction of the left ventricular outflow tract.Both procedures yield equivalent outcomes in the context of isolated valve stenosis (8,9) .
According to biomedical literature, factors leading to an increased risk of reintervention include hypoplastic aortic ring, high post-procedure gradient, other associated left ventricular outflow tract obstruction lesions, aortic valve dysplasia, or the presence of a unicuspid aortic valve.However, aortic valvuloplasty (7) is considered to be safely performed with a significant impact on improving the patient's immediate hemodynamic status.
LV LA LV LA
).Additionally, the same examination revealed left ventricular dilation and hypertrophy, with reduced systolic function (left ventricular ejection fraction: 29%), without septal defects, without aortic coarctation, with normal systemic and pulmonary venous connections.Due to the emergency nature of the patient's condition and having all findings defined by echocardiography, further diagnostic methods were not considered necessary.Through the auxiliary examinations performed, the diagnosis of severe aortic valve stenosis with reduced left ventricular systolic function was confirmed, findings that correlate with the degree of pulmonary compromise found on the chest X-ray.Over a short period of time (hours), the patient experienced clinical deterioration, prompting initiation of mechanical ventilation and inotropic support.At the time of the emergency, the

Figure 4 .
Figure 4. (A) 0.014" guide wire in the left ventricle through the aortic valve (thin white arrow).(B) 6 x 20 mm balloon catheter at maximum inflation (thick white arrow).LV: left ventricle.LA: left auricle